1. Technical Field
The present invention relates to technology for displaying electronic document information that includes markup language data describing predetermined structural elements of the document information; in particular, the invention relates to processing technology for speeding display of document information whose content is described in markup language.
2. Description of Related Art
In electronic data interchange (EDI) of documents, conventionally document content information contains markup language describing standardized structural elements of the document. The markup language usually defines the document content information only in terms of text and structure, as is the case, for instance, with documents described in SGML (Standard Generalized Markup Language). Style definition information (also referred to as a xe2x80x9cstyle specificationxe2x80x9d) necessary for display is managed independently from the document content (text and structure) information. Such documents described in markup language are displayed as follows.
The processing system handling the document to be displayed often effectively represents the document information structure, as written in the markup language in processing memory, by tree configurations of interconnecting nodes. Nodes herein can be understood to be document content elements identified by the components (tags) of the markup language that together fully describe the text and structure of the marked-up document. In thus processing the document information, the tree is sequentially coursed from up-rank nodes to down-rank nodes.
On those occasions when the system in the course of thus processing the document for display reaches a node having a paragraph-forming tag, the absolute display position on the display device of the character data having the offspring nodes of the paragraph-forming tag is determined and display is made.
FIGS. 2-4 illustrate an example of the foregoing. The structure of the marked-up document shown in FIG. 2 is parsed and transformed into structural information forming the tree configuration of nodes shown in FIG. 3. Thereafter, the parsed data of the tree configuration is formatted based on the style specification shown in FIG. 4, and the result is displayed on a subject display device.
To illustrate further, the tree is coursed from structural element xe2x80x9cMEMOxe2x80x9d of node N1, to arrive at structural element xe2x80x9cPARA 1xe2x80x9d of node N2. Only when style definition information designated by this structural element is obtained, can it then be understood whether the structural element is a paragraph-forming element. Herein, among the offspring nodes, nodes having character data (node N25, node N321 etc.) are found, from which display is made calculating absolute display positions on the display device.
With every coursing and arriving at a node within the tree structure having a paragraph-forming element, this is repeated. Consequently, after the display positions of character data contained by up-rank paragraph-forming elements are determined, the display positions of character data contained in down-rank paragraph-forming elements are computed.
With conventional methods of displaying electronic document information structured by markup language, there is a problem, however, with displaying documents having an enormous amount of information. In particular manuals, specifications and the like require a great deal of time to display, because the layout process for the content of the paragraph-forming elements is carried out in order element-by-element from the front of the document.
Further, in network EDI for example, text is displayed based on the content of marked-up document information distributed to and saved by servers on a network. If for example the transfer speed on the communication line to a server into which the text data belonging to a paragraph-forming node is being saved is especially slow, however, a great deal of time will be required until the node text data is in place. Herein, despite the fact that succeeding (down-rank) paragraph node information may be arriving, the processing system displaying the document information does not process the down-rank paragraph node information for display until preceding (up-rank) paragraph node information has been processed for display, which postpones the display process overall.
An object of the present invention is to enable rapid display of electronic documents described in markup language without changing the structure of such a document itself, even wherein the amount of content information of a given document is unusually large. The object is accomplished by a marked-up document visual output method, a computer readable recording medium configured with a marked-up document visual output program in accordance with the method, and a visual output device responsive to the marked-up document visual output program.
To solve the above-explained problems, the present invention in a first aspect is a structured document visual output method for a structured document processing system separately processing markup-language structured document information, and style information defining display style of the structured document information in terms of the markup language.
The structured document visual output method includes the following steps:
(a) A step of determining whether paragraph-forming elements are contained in structured document information being processed for visual output in a display sequence by the structured document processing system, the paragraph-forming elements defining paragraph formation according to the terms of corresponding style information that is available to the structured document processing system.
(b) Wherein paragraph-forming elements are contained in the structured document information, a step of carrying out in response to obtaining of display information for a current paragraph-forming element a paragraph internal layout process determining independently for each paragraph-forming element relative layout within a display information paragraph;
(c) wherein the paragraph internal layout process is completed for the current paragraph-forming element and for all paragraph-forming elements higher ranking in the display sequence than the current paragraph-forming element, a step of determining absolute display positions on a structured document processing system-associated display device for the display information contained in each paragraph-forming element up to the current paragraph-forming element; and
(d) a step of outputting information processed by the structured document processing system in the foregoing steps (a), (b) and (c) as visual output to the system-associated display device.
First a paragraph-forming node designating paragraph formation in terms of the style specification is obtained from among the structural elements of the markup-language structured document information being processed for visual output by the structured document processing system. Next, the method determines whether complementary display information for the current obtained paragraph-forming node is present. If so, the method executes a paragraph internal layout process that computes relative layout, within a corresponding display information paragraph, of all display information for the current paragraph-forming node, independently of layout processes for other paragraph-forming nodes. Herein, relative layout within the paragraph is expressed by relative display position within the region in which the paragraph is laid out. The paragraph internal layout routine is carried out independently for each of the paragraph-forming nodes. In other words, the paragraph internal layout routine for each of the paragraph-forming nodes is not hindered by such factors as display information for paragraph-forming nodes up-ranking from the current paragraph-forming element being not yet completely present, or the display routine being not yet completed for upranking paragraph-forming elements.
The absolute display position on the display device of the paragraph-forming node display information for which the layout routine is finished is determined by the completion of the layout routine for all the paragraph-forming nodes up-ranking from the current paragraph-forming node. In other words, with regard to the paragraph-forming nodes for which the layout routine is finished, the size is found of the paragraph-occupying regions formed on the display device. Further, the start position of the current occupying region is expressed as an absolute coordinate taking the display positional origin as a basis, by summing the heights of all the paragraph-forming nodes up-ranking from the current paragraph-forming node. By utilizing the absolute coordinates of the start positions of the paragraph-forming nodes, the start positions on the display device of the output regions for the display information can be converted into absolute display coordinates taking the display positional origin as a basis. Accordingly, the absolute display position of paragraph-forming node display information for which the layout routine is finished is calculated after all the layout routines for paragraph-forming nodes up-ranking from the current paragraph-forming node are finished, whereupon it is output.
In a second aspect, the present invention is further a visual output method as in the foregoing first aspect, wherein in the foregoing step (b), relative layout within a display information paragraph determined in the paragraph internal layout process is expressed as coordinates taking a position of other display information laid out in the current paragraph as a reference.
The layout of display information within a paragraph is expressed by, for example, coordinates (x, y) that take as a basis a start position within one of the up-ranking display information output region paragraphs.
The invention in a third aspect is a further a structured document visual output method wherein relative layout within a display information paragraph determined in the paragraph internal layout process is expressed as coordinates taking an initial position in the current paragraph layout area as a reference.
The layout of display information within a paragraph is expressed by, for example, coordinates (x, y) that take as a basis the start position of a paragraph-occupying region formed on the display device.
The present invention in a fourth aspect is a computer-readable recording medium configured with a structured document visual output program for a structured document processing system separately processing markup-language structured document information, and style information defining display style of the structured document information in terms of the markup language. The structured document visual output program is for executing:
(a) a step of obtaining from structural elements of markup-language structured document information being processed for visual output in a display sequence by a structured document processing system a paragraph-forming element designating paragraph formation in corresponding style information available to the structured document processing system;
(b) a step of determining whether complementary display information for an obtained current paragraph-forming element is present, and in case complementary display information is not present, storing the current paragraph-. forming element as a standby paragraph-forming element; wherein complementary display information for the obtained paragraph-forming element is present,
(c) a step of executing a paragraph internal layout process for determining relative layout within a display information paragraph of all display information for the current paragraph-forming element, independently of layout processes for other paragraph-forming elements;
(d) a step of determining whether display information complementary to any among the standby paragraph-forming elements is present, and of excluding any such display-information complemented paragraph-forming elements from storage as a standby paragraph-forming elements; and
after the paragraph internal layout process is ended for the current paragraph-forming element and for all paragraph-forming elements higher-ranking in the display sequence than the current paragraph-forming element,
(e) a step of visually outputting the display information processed in steps (a), (b), (c) and (d) of the structured document visual output program for the current paragraph-forming element and for all paragraph-forming elements higher-ranking than the current paragraph-forming element.
In a fifth aspect, the present invention is a structured document visual output system for separately processing markup-language structured document information, and style information defining display style of the structured document information in terms of the markup language, and includes obtain paragraph-forming element means, determination and storing means, layout means, standby excluding means, and output means.
The obtain paragraph-forming element means is for obtaining, from structural elements of markup-language structured document information being processed for visual output in a display sequence by said structured document visual output system, a paragraph-forming element designating paragraph formation in corresponding style information available to the structured document processing system. The determination and storing means determines whether complementary display information for an obtained current paragraph-forming element is present, and in case complementary display information is not present, stores the current paragraph-forming element as a standby paragraph-forming element. The layout means executes a paragraph internal layout process for determining relative layout within a display information paragraph of all display information for the current paragraph-forming element, independently of layout processes for other paragraph-forming elements. The standby excluding means determines whether display information complementary to any among the standby paragraph-forming elements is present, and excludes from storage as a standby paragraph-forming element(s) those paragraph-forming element(s) for which complementary display information is present. The output means visually outputs the display information processed by said structured document visual output system for the current paragraph-forming element and for all paragraph-forming elements higher-ranking in the display sequence than the current paragraph-forming element, after the paragraph internal layout process is ended for the current paragraph-forming element and for all paragraph-forming elements higher-ranking than the current paragraph-forming element.